当备用数据库具有不同的化身（ 查V$DATABASE_INCARNATION ）时，可能会发生这种情况。
每当使用 RESETLOGS 选项（例如闪回、故障转移）打开数据库时，数据库都会创建一个新的化身
例如：
解决方法1：
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--v$archive_gap 的替代SQL
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select USERENV('Instance'), high.thread#, low.lsq, high.hsq
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from (select a.thread#, rcvsq, min(a.sequence#) - 1 hsq
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from v$archived_log a,
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(select thread#, resetlogs_change#, max(sequence#) rcvsq
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from v$log_history
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where (thread#, resetlogs_change#) in
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(select thread#, max(resetlogs_change#)
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from v$log_history
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group by thread#)
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group by thread#, resetlogs_change#) b
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where a.thread# = b.thread#
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and a.resetlogs_change# = b.resetlogs_change#
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and a.sequence# > rcvsq
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group by a.thread#, rcvsq) high,
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(select srl_lsq.thread#, nvl(lh_lsq.lsq, srl_lsq.lsq) lsq
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from (select thread#, min(sequence#) + 1 lsq
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from v$log_history, v$datafile
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where checkpoint_change# <= next_change#
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and checkpoint_change# >= first_change#
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and enabled = 'READ WRITE'
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group by thread#) lh_lsq,
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(select thread#, max(sequence#) + 1 lsq
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from v$log_history
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where (select min(checkpoint_change#)
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from v$datafile
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where enabled = 'READ WRITE') >= next_change#
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group by thread#) srl_lsq
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where srl_lsq.thread# = lh_lsq.thread#(+)) low
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where low.thread# = high.thread#
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and lsq < = hsq
- and hsq > rcvsq;
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如果方法 1 的替代 SQL 仍然没有显示 GAP，请重新创建备用控制文件。这将清除 v$archived_log 中的当前归档日志。
在主库上：
alter database create standby controlfile as '/tmp/ctl_for_standby';
scp到备库上
备库上：
shu abort
改名
mv ctl_for_standby control01.dbf
startup mount
recover managed standby database disconnect;
参考
V$ARCHIVE_GAP doesn't show a existing GAP (Doc ID 974730.1)
Steps to recreate a Physical Standby Controlfile (Doc ID 459411.1)